How to do a grid of animated squares?

[^faldo^]

So I've just finished doing my first 3D film and underestimated how much rolling shutter on my Uni's crappy handycams would ruin me.

So for tomorrow's presentation, i want to explain how rolling shutter actually works to the class with an animation.

I'm trying to make an n*n grid of white squares that become red one after another, and a timecode display underneath it that updates as every CMOS pixel turns on to demonstrate how a CMOS sensor samples over time compared to a CCD. But I can't think of how to do it programatically in After Effects.

I can picture it in bastardised C, something less slap-dash than:

int main(){

    int i, j, n;
    int CMOS[n][n];
    int run = TRUE;

    while(run == TRUE){
        if(timecode.seconds%60 == 0){
            for(i=0; i<n; i++){
                for(j=0; j<n; j++){
                    CMOS[i][j].visability = 0;
                }
            }
        }

        //seconds is actually converted to something of base n^2...
        else{
            i = timecode.seconds%n;
            j = timecode.seconds/n;
            CMOS[i][j].visability = 1;
            printf("%d", timecode);
        }
    }

    return 0;
}

Any thoughts?

 

[milksac]

I would illustrate the bending of an airplane prop to show the effects of rolling shutter.

Use a shape layer to make a a star, tweak the radius and roundness so it roughly resembles a prop. Name the layer Straight Prop.
Animate the prop rotating 30 degrees in 2 seconds.
Add a solid for a background and add a linear wipe effect so it wipes from top to bottom. This represents the progressive scan as the image in captured.
Duplicate your first prop (shape layer) and change the color name the layer Bent prop. Add a twist parameter to the shape layer to bend the prop. You'll need to tweak the rotation to keep the straight prop and bent prop in sync.
Add a linear wipe effect to both layers so that the Bent prop wipes on as the Straight prop wipes off.

Either before or after the AE illustration you can show the students some of the many clips on youtube of CMOS video bending airplane props.